WO 2013/099093 A1 (hereinafter referred to as D1) discloses a sound field control device configured to reproduce a desired sound in a listening area and mitigate that sound in an area surrounding the listening area. The sound field control device disclosed in D1 includes a control filter and a listening correction filter.
The listening correction filter performs signal processing on an input signal from a sound source in accordance with a preset control characteristic, thus generating a second output signal and outputting the signal to a second speaker. The control filter performs signal processing on the second output signal supplied from the listening correction filter in accordance with the preset control characteristic, thus generating a first output signal and outputting the signal to a first speaker.
The control filter has a control characteristic in which, by means of a sound played back from the first speaker, a sound played back from the second speaker is reduced in an area surrounding the listening area. The listening correction filter has a control characteristic in which, by means of the sounds played back from the first and second speakers, a sound having a specified target acoustic characteristic emerges in the listening area.
The sound field control device (sound reproduction system) disclosed in D1, however, could make the desired sound (corresponding to the “first sound”) audible to not only a person in the listening area (corresponding to the “first region”) but also a person in an area surrounding the listening area (corresponding to the “second region”) as well.